1. Field of the Invention
The present invention relates to the use of carboxyl-containing reaction products of proteins or protein hydrolyzates which have been hydrolyzed no further than the dipeptide stage as ingredient of detergents and cleaners.
2. Discussion of the Background
Z. Chem. 25 (1985), 18-19, discloses the reaction of amino acids or peptides with maleic anhydride in acetic acid.
JP-A-56/012 351 discloses reaction products of amino acids and maleic anhydride or succinic anhydride, which are prepared in organic solvents. The reaction products are used for example in shampoos or cleaners.
EP-A 0 455 468 discloses detergent formulations which contain chemically modified vegetable proteins as grayness inhibitor. The proteins are preferably modified by reaction with phthalic anhydride in an aqueous medium at a pH of at least 8. However, the degree of the modification of the proteins is relatively small, so that the reaction products have virtually no dispersing effect and do not enhance the primary detergency when used in detergents.
DE-A-4 033 209 describes the reaction of protein hydrolyzates having a molecular weight of from 200 to 20,000 with ether carbonyl chlorides in an aqueous medium. The reaction products are used as surfactants in detergents and cleaners.
EP-A--0457205 discloses the use of water-soluble or water-dispersible grafted proteins as ingredient of detergents and cleaners in amounts from 0.1 to 20% by weight, based on the respective formulations. The grafted proteins are prepared by free-radically initiated copolymerization of monoethylenically unsaturated monomers in the presence of proteins.